Conductive foils made of an elastically malleable, non-conductive carrier foil strip having printed circuit traces that are insulated to the outside and that run in the longitudinal direction of the carrier foil strip are used, for example, in motor vehicles to connect various electrical/electronic components to each other. The conductive foils are composed of a carrier foil made of, for example, polyamide, onto which are applied thin printed circuit traces of copper, which are covered by an insulating material, for example a further insulating foil or an insulating enamel. At the ends of the strip-shaped conductive foil, contacting devices can be arranged which are often configured as soldering eyelets and are soldered to connector pins of electrical or electronic components. Conductive foils of this type are known, for example, from German Patent No. 197 19 238. The conductive foils are elastically malleable and thus are relatively insensitive to vibration and stress due to shaking.
However, it is disadvantageous that the known conductive foils are flaccid, so that it is not possible to give the conductive foils a lasting two-dimensional or three-dimensional shape by manual or machine bending. This disadvantage makes it more difficult to install the conductive foil in electrical apparatuses, since the flaccid conductive foil must continuously be held steady during assembly, and fasteners are potentially necessary to secure the conductive foil on the housing walls or support framework in electrical apparatuses.
As a result of the conductive foil according to the present invention, these disadvantages are avoided. The conductive foil advantageously has at least one lastingly malleable shaping element, extending in the longitudinal direction of the carrier foil strip and applied to the carrier foil strip of the conductive foil so as to be insulated from the printed circuit traces. The shaping element can be arranged on the carrier foil in a simple and economical manner, and it advantageously makes it possible to give the conductive foil a lasting two- or three-dimensional shape. By xe2x80x9clastingxe2x80x9d in this context, it is understood that the two- or three-dimensional shape of the conductive foil does not change by itself during transport or assembly but can be changed by a fresh manual or machine bending of the shaping element. It is particularly advantageous that as a result of the flexural stiffness of the conductive foil resulting from the shaping element, manual or machine processing of the conductive foil is dramatically simplified. The known manufacturing process of conductive foils, advantageously, needs to be changed only slightly. Since the shaping element runs in the longitudinal direction of the carrier foil strip in the same direction as the printed circuit traces, the conductive foil can be advantageously unrolled in the longitudinal direction. Then, as needed, pieces of various lengths can be cut from the roll and processed further. In the unrolling and rolling up, it is true, a certain resistance must be overcome resulting from the fact that the shaping element is curled up or stretched out, but in view of the advantages described above, this is entirely acceptable.
It is particularly simple to manufacture the at least one shaping element out of metal. For example, the shaping element can be a single metal wire running in the longitudinal direction of the carrier foil strip, the metal wire being introduced as an insertion part in the conductive foil or being bonded to the carrier foil strip, making the manufacturing of the conductive foil only somewhat more expensive. The metal wire can be made of very inexpensive material, raising the manufacturing costs of the conductive foil only slightly. As a result of a manual or machine bending of the metal wire arranged in the conductive foil, the conductive foil, in a very simple manner, can be given a lasting shape and the installation of the conductive foil, for example in the apparatus housing of an electronic control unit, can be made significantly easier. Two metal wires running in the longitudinal direction of the carrier foil strip can advantageously be arranged on the conductive foil. As a result, it is particularly easy to give the conductive foil a three-dimensional shape.
The shaping element, however, can also be a metal foil applied to the carrier foil strip, the metal foil having sufficient thickness to make possible a lasting malleablility of the conductive foil.